1. Field of the Invention
The present invention relates generally to ink cartridges and inkjet printers. In particular, the present invention is directed towards ink cartridges and inkjet printers, in which when ink drips from an ink supply portion of the ink cartridge, a protrusion receives the ink and retains the ink because of a capillary force created by grooves or holes formed in the protrusion.
2. Description of Related Art
A known inkjet recording system, such as the inkjet recording system described in JP2005-238815, includes an inkjet recording apparatus and a plurality of ink cartridges mounted side by side to a mounting portion of the inkjet recording apparatus. An ink supply opening is formed at one surface of the ink cartridge. An ink supply needle provided in the inkjet recording apparatus, is inserted through the ink supply opening when the ink cartridge is mounted to the inkjet recording apparatus, and ink within the ink cartridge is supplied to the inkjet recording apparatus. The ink cartridge includes a case, and a bag positioned within the case. The bag has a port for supplying ink within the bag to the outside of the ink cartridge, and the port is aligned with the ink supply opening. Within the port, a lid, a valve, and a spring are provided. The spring urges the valve, such that the valve contacts the lid. When the valve contacts the lid, the inside of the bag and the outside of the ink cartridge are not in fluid communication with each other. Nevertheless, when the ink supply needle pushes the valve against the urging force of the spring and the valve separates from the lid, the inside of the bag is in fluid communication with the outside of the ink cartridge.
Ink adheres to the ink supply needle after the ink supply needle is inserted into the ink cartridge through the ink supply opening. The ink adhering to the ink supply needle adheres to an area adjacent to the ink supply opening when the ink cartridge is removed from the mounting portion. The ink may drip from the ink supply opening on to the mounting portion. If the ink drips from the ink supply opening on to the mounting portion, the mounting portion becomes dirtied. In addition, ink may drip from the ink supply needle on to the mounting portion. After the mounting portion becomes dirtied, when a new ink cartridge is mounted to the mounting portion, the new ink cartridge also becomes dirtied. When a user of the inkjet recording system removes the new ink cartridge from the mounting portion, a hand of the user also may become dirtied. This is problematic, especially when the communication between the inside of the ink cartridge and the outside of the ink cartridge is prohibited by the valve urged by the spring. When the ink supply needle is removed from the ink supply opening, the spring pushes the valve back toward the ink supply opening. Therefore, ink is pushed by the valve toward the ink supply opening. A large amount of ink may be pushed out of the ink supply opening.
Another known ink cartridge includes an ink supply portion extending from one surface of the ink cartridge. An ink supply opening is formed at the end of the ink supply portion. Ink also may drip from the ink supply opening of this type of ink cartridge on to a mounting portion of an inkjet recording apparatus.